Exemplary embodiments of the invention relate to a steering spindle arrangement of a motor vehicle on the interface of the steering spindle with the steering coupling.
Currently direct screwing of the bottom of the steering spindle with the steering coupling is only possible in the combined field of exhaust gas assemblies, catalytic converters, engines and transmission lines with considerable effort. Here, the steering spindle is screwed in at the bottom with the steering coupling transverse to the steering spindle direction. On the one hand, this has the disadvantage of poor accessibility, and on the other hand the number of variants for optimizing the accessibility for different engine types and steering assemblies, for example left-hand and right-hand drive steering models, is increased, and, in addition, standard assembly sequences, such as the time of assembling the exhaust gas assembly, are hardly or not at all adhered to. In another approach regarding the configuration of the device, the steering coupling part is dispensed with and only the steering spindle at the bottom is used, wherein, however, a start-up of the engine in the Z direction during the final assembly, so the conflation of the pre-assembled engine/transmission and chassis unit, is, disadvantageously, not possible.
German patent document DE 10 2008 006 497 A1 describes an assembly arrangement for connecting a steering spindle to a steering coupling. The end piece of the steering spindle is inserted into an end receiving region of the steering coupling, wherein the assembly arrangement comprises a device for fundamentally achieving the coaxial alignment of the steering spindle and the steering coupling. Thus, the automatic conflation of the steering spindle with the steering coupling is enabled, since a manual, coaxial alignment of the steering spindle and the steering coupling can be avoided. To that end, the steering spindle has a hooking element at the end, into which a strap loop protruding from the end receiving region of the steering coupling is mounted before the final assembly. By pulling on the loop of the strap, the hooking element, together with the end piece of the steering spindle, is inserted into the end receiving region of the steering coupling so as to be screwed in there.
German patent document DE 10 2005 006 251 A1 addresses the problem of simplifying the assembly of a steering spindle on a motor vehicle. To that end, the steering spindle, which can be connected at one end to a steering wheel and at the other end to a steering gear via a steering coupling, has a cylinder body and a piston rod body inserted telescopically therein. The steering spindle has a pneumatic connection in communication with a cylinder chamber arranged in the cylinder body and axially delineated by the piston rod body, wherein the piston rod body is driven out from the cylinder body by an application of pressure on the cylinder chamber. Thus, the spindle end provided for the connection to the steering coupling does not have to be drawn into the engine bay by hand, but can rather be introduced into the engine bay by the application of pressure without it being necessary to touch said spindle end. Here, the steering spindle end and steering coupling are also screwed in transversely to the steering spindle direction.
German patent document DE 102 39 202 B4 discloses a connection between a steering shaft and a steering gear in a motor vehicle with a divisible joint, whereby the assembly and disassembly processes are simplified. To that end, the joint has an extension that can be fed, for assembly, through an opening in the footwell of the motor vehicle and which is equipped with protrusions, the joint being able to be inserted without rotation into a moveable cup-shaped or tulip-shaped receiver, which is located outside the footwell relative to the extension and which extends in the direction of the footwell. The joint is embodied as a tripod joint, wherein the extension has a tripod head with three segments extending radially away from the extensions, the segments engaging with corresponding grooves of the receiver.
Due to the tight construction space conditions, the steering train normally impedes the assembly of the engine module with the body. The provision of an intermediate piece, which connects the steering coupling to the end of the steering spindle, enables this to be able to be swivelled away in the loose state, i.e. unscrewed, at the interface at which it is screwed in with the end of the steering spindle, in order to simplify the assembly of the engine module. The steering spindle can be pushed back to some extent in the steering wheel direction. After the assembly of the engine, the intermediate piece must be reconnected to the end of the steering spindle. This is extremely difficult for the assembler, since the construction space for a manual operation hardly leaves any clearance and the connection partners are very difficult to detect optically.
Exemplary embodiments of the present invention are directed to simplifying the conflation of steering spindle end and steering coupling, as well as creating an arrangement that enables the conflated steering spindle and steering coupling ends to be connected to each other in the correct relative position and thus for a defective assembly to be prevented.
A first embodiment of the invention relates to a steering arrangement that has a steering spindle with a steering spindle connection, which is connected to a fork crown of a steering coupling via an intermediate piece, wherein the steering spindle connection and the intermediate piece are formed as plug partners on ends, which face each other, by means of at least one tongue and groove guide element pair that provides a torque-transmitting priority control. Each plug partner, steering spindle connection and intermediate piece thus has a groove or a corresponding tongue as the at least one guide element. The groove and tongue of the at least one tongue and groove guide element pair are positioned in the longitudinal axial direction on the steering spindle connection and the intermediate piece, wherein the steering arrangement comprises a clamping device that clamps the plug partners to each other in a plugging position.
Due to the guide elements according to the invention, which can be readily touched or optically perceived by an assembler, the steering spindle and the intermediate piece of the coupling may, in an advantageously simpler manner, be combined, wherein they always assume the correct relative position to each other due to the pre-determined guiding. The clamping device connects the plug partners by means of contact pressure force in such a way that undesired release of the plug partners during the vehicle operation is prevented. The guide elements formed by groove and tongue extend solely along the steering spindle axle. Therefore, a clamp-free manageability of the plug partners, which is easy for the assembler to embody, is enabled for achieving the plug connection.
The groove and tongue of the at least one tongue and groove guide element pair preferably have a tapered shape, wherein the groove tapers in the longitudinal axial direction towards the side facing away from the plug partner, and the tongue tapers in the longitudinal axial direction towards the side facing the plug partner.
In one embodiment, the groove(s) are provided on the steering spindle connection and the tongue(s) are provided on the intermediate piece. Thus, the at least one, preferably several, particularly preferably three grooves arranged with 120° displacement to one another are provided on the cylindrical exterior of the end of the steering spindle connection facing the intermediate piece, while one or more tongues are provided on the cylindrical interior of the intermediate piece. The number of grooves can thus be greater than the number of tongues, such that, for each tongue of the intermediate piece, at least one groove is present on the steering spindle connection. Naturally, it is generally also conceivable to provide the grooves in the intermediate piece and the tongues on the steering spindle connection, or to arrange both on both plug partners interchangeably.
Furthermore, the grooves on the steering spindle connection on its end facing away from the intermediate piece flow into a recess or an annular groove, the radial depth of which corresponds to or is greater than a groove depth.
The steering spindle connection and the intermediate piece preferably have tongue and groove guide element pairs designed with different widths and/or are distributed asymmetrically over the periphery of the steering spindle connection and the intermediate piece. A clear allocation of the tongue/groove guide elements of the plug partners is hereby possible, such that a defined relative position of the steering spindle connection and the intermediate piece with respect to each other is defined and no defective plug connection can take place during assembly. In the case of a symmetrical arrangement on the cylindrical exterior of the steering spindle connection and the interior of the intermediate piece, three respective grooves and tongues are, as mentioned above, arranged with 120° displacement to one another. The number of grooves can thus be greater than the number of tongues, such that, for each tongue of the intermediate piece, at least one groove is present on the steering spindle connection. Naturally, it is generally also conceivable to provide the grooves in the intermediate piece and the tongues on the steering spindle connection, or to arrange both on both plug partners interchangeably. With a plurality of grooves and tongues, the ability of the plug partners to transmit higher levels of torque is also improved.
A sleeve that can be moved relative to the intermediate piece is arranged around the intermediate piece, the sleeve having, on a steering spindle end side of the sleeve, one or more gearing segments extending radially inwards from the edge of the sleeve, which engage with the recess or annular groove in the plugging position, which recess or annular groove forms a stop with its coupling-side edge.
The clamping device, by means of which the plug partners can be clamped to each other in the plugging position, comprises a downwardly extruding annular collar of the intermediate piece, a helical spring arranged around the intermediate piece and a guide device, having at least one guiding pin, arranged for axial movement on the intermediate piece. The annular collar extends radially outwards on the steering-spindle-side end of the intermediate piece, wherein the helical spring arranged around the intermediate piece is supported at one end on the annular collar. At the other end, the helical spring is supported on the guiding pin.
The guide device can be a clamping sleeve, from which the guiding pin extends radially outwards, and which, furthermore, in a peripheral region, engages with a spring tongue that is penetrated by a locking pin and has a second guiding pin extending radially inwards, and which engages with a longitudinal groove that is introduced in the longitudinal axial direction in the exterior of the intermediate piece. The inner guiding pin, which runs in this longitudinal groove, ensures that the clamping sleeve is only moved axially. The guide device can alternatively have a ring or ring segment as an essential feature, which has holes at two diametrically opposite points that receive a bolt that forms the guiding pin.
Provision can furthermore be made for the intermediate piece to taper on the coupling-side end facing away from the annular collar in a stepped recess, which approximately corresponds to a ramp shape of the coupling-side end of the steering spindle connection. In a region of the intermediate piece that is close to the recess, a slot can, on the one hand, be formed in the section between the recess and the annular collar, through which the locking pin extends and, on the other hand, the longitudinal groove can also be arranged in the region of the intermediate piece in the section between the recess and the annular collar, wherein it preferably breaks through the annular collar, such that the arrangement of the clamping sleeve is simplified with the inwardly-pointing guiding pin.
The sleeve enclosing the intermediate piece, the guide device and the helical spring can furthermore have at least one slot forming a guide runner for the radially outwardly-extending guiding pin of the guide device. This slot can run helically.
In a further embodiment, the intermediate piece can comprise a control pin extending from a peripheral surface of the annular collar. To that end, the control pin can be arranged in a bore-hole in the peripheral surface. The control pin can then engage with a further slot in the sleeve, which is formed in the steering-spindle-side end region of the sleeve as a guide runner. This slot particularly has a first track section in the peripheral direction and a second track section running at right angles to the first track section in the axial direction with respect to the steering-spindle-side end of the sleeve.
Alternatively to the control pin and the runner thereof, the sleeve can have a cam on its interior behind each gearing segment, which is displaced radially backwards with respect to the gearing segment and which, in the plugging position in which the gearing segments engage behind the coupling-side edge of the recess/annular groove, engage with a depression in the annular collar. Furthermore, for each cam, a trough-like impression is formed on a front side of the intermediate piece as transportation security, with which the cam engages in a transportation arrangement of the steering arrangement. Thus, the components are protected from misuse by the transportation security apparatus up to the point of assembly.
In addition, the steering arrangement can, according to a further embodiment of the invention, have a further depression in the sleeve, adjacent to one of the gearing segments, the depression displaying a security ring contour or comprising an embedded retainer ring. A pin extending axially from the front side of the intermediate piece can be incorporated into this depression or into the retainer ring embedded in the depression, if the cam locks into the depressions of the annular collar. For this, the pin has a contour corresponding to the security ring contour of the depression or the retainer ring embedded therein. A secure connection of the plug partners, and thus the steering spindle, is guaranteed by this mechanical positive fit, even if the pre-stressing elements fail.
Defective assemblies are advantageously prevented by the plug connection according to the invention; furthermore, clearance caused by wear can be compensated for up to a certain degree.